Wi-Fi is a wireless technology associated with the Wi-Fi Alliance and improves the interoperability of local area network products based on the IEEE 802.11 standards. The IEEE 802.11 Wireless Local Area Network technology is a commonly available technology that is being integrated with wireless communication devices referred to as dual-mode, tri-mode, and more generally a “multi-mode” wireless communication devices. An illustrative dual mode phone includes a Wi-Fi/CDMA or Wi-Fi/GSM mobile phone.
A multimode wireless communication device is a device that combines at least two different communication access technologies (CATs). The CATs may operate at different frequencies and may operate using different wireless standards, even though the CATs operate within the same frequency band. For example, a multimode handset may support cdma2000 and GSM at 800 MHz, and in a particular market having an A side operator and a B side operator there may be a combination of cdma2000 and GSM. Wireless communications devices that support multiple CATs, e.g. CDMA2000, WCDMA, GSM, and Wi-Fi, must determine the appropriate CAT to acquire the available CAT.
Currently, multi-mode wireless communication devices that include Wi-Fi technology have a major setback, namely, the high power consumption by the Wi-Fi component eventually leads to a reduced battery life. The 802.11 WLAN Medium Access Protocol (MAC) protocol defines only two operational modes, in which a mobile can operate, namely, active mode and power saving mode.
A Wi-Fi module housed in a wireless communication device operates in either an awake state or a doze state. In an awake state, the Wi-Fi module can transmit, receive or sense the physical channel, and it actually continues to sense the channel unless it either transmits or receives a frame. In doze state, the Wi-Fi module is not able to transmit or receive, and consumes very little energy. The Wi-Fi power management module determines how a Wi-Fi module switches between the awake state and doze state. With respect to a multimode wireless communication device, the Wi-Fi power management module operates independently of the other CATs and network communications with various CATs.
Cellular technologies such as Code Division Multiple Access (CDMA) automatically switch to power-save mode if the wireless device has not found a signal after a predetermined period of searching, e.g. 15 minutes. Power save mode decreases the drain on the battery. When the phone is in power save mode, it decreases the drain on the battery. When the phone is in power save mode, you cannot make calls and the no signal icon appears on the screen. The phone periodically rechecks for a signal. Typically, the user can press any key to check for service. Generally, when the phone finds a signal, the phone automatically switches out of the power-save mode and displays the signal strength icon.
Current multimode wireless communication devices have dedicated CAT circuitry that meets the requirements set forth by standard performance requirements. Generally, these standards operate independently of one another. Thus, each CAT module in the multimode wireless communication is actively attempting to communicate with a CAT network becomes a drain on system resources such as the battery.
By way of example and not of limitation, for a dual mode Wi-Fi/CDMA communication device, the CDMA mode has a power management module that is dependent on network communications. Although, the Wi-Fi mode does have power management for the mobile handset, the Wi-Fi power management module operates independently of the CDMA power management module and consumes additional power resources.
Thus, there is a need for an integrated power management module for a dual mode Wi-Fi/CDMA communication device that overcomes the limitations of high power consumption, reduced battery lifetime, and that can be integrated with the firmware of the dual mode wireless communication device.